So say the biggest index providers, who have no plans to alter the composition of their benchmarks after Britain chose to exit the European Union. The nation’s shares will stay in the MSCI Europe Index as membership in the trading bloc has no bearing on the gauge’s make-up, said Remy Briand, MSCI Inc.’s global head of research. They’ll also continue to be eligible for global and regional measures at Stoxx Ltd., overseer of the Stoxx Europe 600 Index, according to a company spokeswoman.

Index providers look at liquidity, transparency and market capitalization to select stocks for equity gauges, and membership in regional alliances usually isn’t a consideration. However, if trading conditions are affected by political or other events, they’ll review the composition of their benchmarks -- something that happened last year when Greece shut down its market.

“This is a very severe market event, but we are not adjusting our indexes on market events,” Briand said, referring to Britain’s referendum result. “The markets are fully functional. We are monitoring the situation, but there is no change of plan right now.”

Britons’ vote last Thursday to secede from the 28-nation bloc triggered a selloff in financial markets, wiping about $1 trillion off the value of global equities and raising concerns that an already-fragile global economic recovery will falter. European equities saw their worst two days since 2008 before rebounding on Tuesday, and volatility may persist in coming months as Britain negotiates its relationship with the EU. S&P Global Ratings and Fitch Ratings cut their U.K. credit ratings, while Moody’s Investors Service lowered its outlook on the country to negative from stable.

A spokeswoman at London Stock Exchange Group Plc, which owns FTSE Russell, declined to comment on potential index changes. The MSCI Europe Index and Stoxx 600 both include companies from Switzerland and Norway, which are not part of the EU.

Beyond index composition, the populist sentiment that drove Brexit to victory is something MSCI is monitoring as part of its role as a consultant on systemic portfolio risk. The firm is stress testing the impact on institutional funds and will publish a report in July, Briand said. He declined to provide more details before its release, though he said initial results point to additional shocks for investors if the sentiment intensifies.

“What triggered this vote has some commonalities with the rest of Europe and the U.S.,” he said, referring to the U.K. referendum. “It has the potential to affect markets across Europe and the U.S. -- overall it’s a negative impact.”

The U.K. result comes amid a busy calendar of European elections over the next 18 months. France goes to the polls next April, with the far-right National Front expected to make a strong showing. The Dutch will vote by March, and Germany holds federal elections in the autumn of 2017. The U.S. has its own vote this year, with Republican Donald Trump probably facing Democrat Hillary Clinton.

For its study, MSCI selected the countries where it expects populist pressure to continue, using a model to forecast their economic growth and inflation rates in accordance with assumptions based on past policies and current proposals from the movements. It then tested the performance of investor portfolios under the new conditions.

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